This is the user interface of Instantbird. http://www.instantbird.com/
Select a component to see open bugs in that component:
The account manager window
The account wizard that you see when you create a new account or when you start Instantbird the first time.
The main Contacts window including the list of all Contacts and the Conversations on Hold.
The conversation window or thing displayed in the conversation itself
Official add-ons from Instantbird team found at hg.instantbird.org/addons (this is not for all add-ons, only ones provided by the developers of Instantbird!).
l10n and i18n issues.
Anything that doesn't fit in any of the components
The preferences window